Archive

This post is in honour of a great mind where I have more to say sometime.

The late Vít Klemeš who died 2010 gave a talk on July 12, 2007, in the HW2003 Workshop on Analysis of Variability in Hydrological Data Series, at the IAHS General Assembly in Perugia, Italy.

He concluded with a truism I believe in

The moral of my talk is this: The most fun and perhaps the greatest value of doing something is in doing it. The results may well go up in smoke, be wrong, become obsolete and forgotten, but some new ideas may have emerged in pursuing them, and some of them may somewhere, sometime, bear fruit. …”

They have, right now.

And that is Vít Klemeš. He had a sense of fun, sense of humour, yet enough is revealed in past writing showing he comes across as quietly subtle, a real technician, the lack of ego which comes with confidence.

This presentation is as a PDF at a moderate technical level which might seem somewhat wooden in places. It needs a degree of background knowledge, without this maybe there is enough.

The UK Met Office / Hadley Centre (Met Office) / Climatic Research Unit (UEA) construct and publish global time series for temperature based on published 5 degree gridded. How this is derived from land meteorological station readings and ship board for sea surface temperature is unclear. The gridded to eg. global is a simple (cosine) weighted average which takes into account the variable area of a linear grid representing a sphere.

I have put together maps showing the data counts for decades over a world shore outline. These are provided as vector plots (master work), PDF, or for casual looks, PNG. The results are disturbing and particularly in the light of the Met Office producing 100 different versions of HadSST3. “Each of the following files is a zip archive containing ten realisations of the HadSST3 data set. There are 100 realisations in total.”

I’ve known for a number of years of the dreadful state of climatic datasets, HadSST being one of those but did not have the pictorial evidence. Period from 2005 is an arbitary choice arising during software development.

When I first looked at the gridded SST data, some time before 2010 I noticed what seemed to be a mix of monthly and annual in cells, with many missing data. It also looked very dubious on coastline handling. This was noted but nothing further done.